The present invention relates to a large-capacity storage apparatus for use in an information processing apparatus and particularly to a disk storage apparatus employing a hard disk as a disk-like recording medium both sides of which data can be read from and/or written in, and a rotation actuator.
A disk storage apparatus 101 having an arrangement shown in FIGS. 33, 34 has been proposed as a high-speed large-capacity disk apparatus such as, typically, a removable hard disk apparatus related to the present invention. A disk cartridge 120 having an arrangement shown in FIG. 35 has been proposed as a disk cartridge accommodating a hard disk as a recording medium for use in the above disk storage apparatus 101.
As shown in FIG. 33, the disk storage apparatus 101 is formed of, as main mechanical elements, a disk rotating mechanism 104 equipped in a disk cartridge loading portion 103 having an insertion slot 103a at a front surface of a front half portion side of a main chassis 102 and a reading/writing head mechanism 105 disposed at a rear half portion side of the main chassis 102.
The disk rotating mechanism 104 is mounted on a subchassis (not shown) disposed below the main chassis 102 so as to be lifted up and down thereby and so that a spindle motor 108 having a chucking magnet 107 should be projected by a predetermined height or lower from an opening 106 formed through a bottom surface center portion of the disk cartridge loading portion 103.
In order to downsize the apparatus 101, the reading/writing head mechanism 105 is positioned on the rear half portion side of the main chassis 102 and in the vicinity of the disk cartridge loading portion 103. The reading/writing head mechanism 105 has a reading/writing head (hereinafter referred to as an R/W head) H attached through a suspension 112 formed of a plate spring at a tip end of an actuator arm 111 pivotally supported by a shaft 109 and rotated by an actuator 110.
The actuator 110 of the reading/writing mechanism 105 is formed of a movable coil 110a fitted to a rear end portion of the actuator arm 111, a flat magnet 110b fixed on the main chassis 102 side so as to correspond to the movable coil 110a, and a yoke forming a magnetic circuit (not shown). The R/W heads H are a pair of upper and lower heads. Therefore, a pair of upper and lower suspensions 112a, 112b are employed as the suspension 112 fitted to the tip end portion of the actuator arm 111. Both of the suspensions 112a, 112b are fitted to the actuator arm 111 at an interval therebetween so as to be projectingly extended in the extended center line of the actuator arm 111. The R/W heads H are bonded to sliders fitted to inner surface sides of tip ends of the both suspensions 112a, 112b in the direction perpendicularly to center lines of the suspensions 112a, 112b, being opposed to each other in the vertical direction. Moreover, load bars 113 are fixed on outer surface sides of the tip ends of the both suspensions 112a, 112b so as to be projected in the direction extended from the tip ends.
The reading/writing head mechanism 105 is located in a state that the tip ends of the actuator arm 111 including the suspensions 112a, 112b are opposed to the inside of the disk cartridge loading portion 103, and is inserted into a disk cartridge 120 to be loaded. Therefore, in order to prevent the tip end of the actuator arm 11 from disturbing a hard disk housed in the disk cartridge 120, the tip end portion of the actuator arm 111 is forked, i.e., branched to upper and lower piece portions. The suspensions 112a, 112b are respectively attached to the upper and lower piece portions.
A ramp 114 which is a slide-shaped block serving as a guide for the R/W heads H is fixed on the rear half portion side of the main chassis 102 in the vicinity of the disk cartridge loading portion 103 and ahead of the actuator arm 111 so as to be opposed to an inside of the disk cartridge loading portion 103. This ramp 104 is also inserted into the disk cartridge 120 to be loaded and hence is forked, i.e., concave-shaped in order to be prevented from disturbing the hard disk. The load bars 113 at the tip ends of the suspensions 112a, 112b are brought in slidable contact with upper and lower surfaces of the ramp 114, respectively, thereby the suspensions 112a, 112b, i.e., the R/W heads H being held at an interval.
Moreover, a printed circuit board 115 mounted with a control circuit for controlling the actuator 110, a reading/writing amplifier for the R/W heads and so on is disposed on the rear half portion of the main chassis 102, being connected through a flexible wiring plate 116 to the actuator arm 111 side.
As shown in FIGS. 33, 35, the disk cartridge 120 is formed of rectangle-shaped upper and lower halves 121, 122 and a magnetic disk on both sides of which data can be read from and written in, i.e., a hard disk 124 rotatably accommodated in a disk accommodating portion 123 between the upper and lower halves 121, 122. A hub 125 made of a ferromagnetic material is fitted to a center portion of the hard disk 124 and opposed to a center aperture 126 formed through the lower half 122.
An opening portion 127 into which the tip end portion of the actuator arm 111 is inserted together with the suspensions 112a, 112b attached with the R/W heads H is formed at both of the upper and lower halves 121, 122 on the front surface side of the disk cartridge 120. A shutter 128 for opening and closing the opening portion 127 is attached to the opening portion 127. The shutter 128 is pivotally and rotatably supported by a shaft 129 of the upper half 121. When the disk cartridge 120 is not in use, the shutter 128 closes the opening portion 127 to prevent dust, fingers and so on from being inserted into the disk cartridge 120. When the disk cartridge 120 is loaded into the disk storage apparatus 101, the shutter 128 is automatically opened.
As shown in FIG. 33, when the disk cartridge 120 is loaded onto the disk storage apparatus 101, the disk cartridge 120 is horizontally inserted into the disk cartridge loading portion 103 disposed on the front half portion side of the main chassis 102 through the front surface insertion slot 103a with its opening 127 being opposed to the front surface insertion slot 103a. Initially, the shutter 128 is automatically opened by a shutter opening and closing mechanism (not shown), and hence the opening portion 127 is exposed to the outside. When the disk cartridge 120 is inserted and moved to a predetermined position, as shown in FIG. 34, a part of the actuator arm 111 from its tip end portion to the both suspensions 112a, 112b and the slide-shaped portion of the ramp 114 are moved through the opening portion 127 into the disk cartridge 120, a part of an outer periphery portion of the hard disk 124 is located in the concave portion of the ramp 114. In this state, since load bars 113 are in contact with a high position portion of the ramp 114, the suspensions 112a, 112b are held across an extended interval, thereby the R/W heads H being located across an interval which is larger than a thickness of the hard disk 124.
In this state, the spindle motor 108 of the disk rotating mechanism 104 is lifted up and projected from the opening 106 at the bottom-surface center portion of the disk cartridge loading portion 103 by a predetermined height. The spindle motor 108 attracts the hub 125 of the hard disk 124 through the center aperture 126 of the lower half 122 by an attraction magnetic force of a chucking magnet 107. Then, the spindle motor 108 and the hard disk 124 are moved integrally, i.e., the hard disk 124 is chucked by the spindle motor 108.
Then, when the spindle motor 108 is rotated and its rotation speed becomes a certain angular velocity, the actuator arm 111 is rotated in the direction toward the inside of the disk cartridge 120, i.e., in the direction toward the hard disk 124 by the actuator 110, and then the load bars 113 of the both suspensions 112a, 112b are slid down on the ramp 114 from its higher position side to its lower position side. Consequently, the R/W heads H are gradually brought into their landing states on the hard disk 124. In this landing operation, when the hard disk 124 is rotated, an aerodynamic effect produced between the hard disk 124 and a slider supporting the R/W heads H, i.e., a so-called air film produced between the surface of the rotating hard disk 124 and the slider floats the slider over the hard disk 124 across an interval of several tens of nm, and hence prevents the R/W heads H and the hard disk 124 from being in contact with each other.
In this state, the actuator arm 111 is rotated to position the R/W heads H to a predetermined track, and then information is read out from and/or written in the hard disk 124.
Since in the disk storage apparatus thus arranged the actuator arm 111 for moving the R/W head H and the ramp 114 moving the R/W head H moved close to and away from the hard disk 124 are disposed so as to be opposed to the disk cartridge loading portion 103, it is impossible to carry out a pop-up type loading and unloading operation for loading and unloading the disk cartridge 120 onto and from the disk cartridge loading portion 103, and hence, in order not to interfere with the actuator arm 111 and the ramp 114, the disk cartridge 120 must be inserted into the disk cartridge loading portion 103 with being in parallel to a bottom surface portion of the disk cartridge loading portion 103 and with an opening 127 being opened. Therefore, when the disk cartridge 120 is inserted into and ejected from the disk cartridge loading portion 103, the bottom surface portion of the disk cartridge loading portion 103 must be kept so as to be a plane having no projection.
Accordingly, the spindle motor 108 for attaching and rotating the hard disk 124 in the disk cartridge 120 on the bottom surface of the disk cartridge loading portion 103 must be lifted down from the bottom surface of the disk cartridge loading portion 103 when the disk cartridge 120 is inserted and ejected. In order to lift the spindle motor 108 up and down as described above, a supporting mechanism for supporting the spindle motor 108 must require safety and reliability, which complicates an arrangement of the supporting mechanism and increases the manufacturing costs thereof.
The actuator arm 111 is formed to be fork-shaped in order not to interfere with the hard disk and has suspensions for supporting the R/W heads H 112 fitted to its tip end portions so as to be extended in a center line thereof. Thus, the actuator arm 111 has an in-line arrangement. Since the actuator arm 111 is pivotally attached to a position in the vicinity of the disk cartridge loading portion 103 in order to downsize the disk storage apparatus, the actuator arm 111 must be inserted into the disk cartridge 120 loaded onto the disk cartridge loading portion 103 with its portion from the suspensions 112 at its tip end portions to a pivot portion thereof being inserted into the disk cartridge 120 from its side surface side. Consequently, the disk cartridge 120 must be formed with its opening portion 127 being set larger, which considerably restricts a shape of the disk cartridge and also restricts a freedom of a design of a structure. Therefore, it is difficult to manufacture a desired disk cartridge.
The ramp 114 is formed so as to be fork-shaped in order not to interfere the hard disk. Since the ramp 114 must be located away from both surfaces of the hard disk at an interval, an interval between the suspensions 112 must be spread wider, which results in that the ramp 114 is inevitably formed so as to be thick. As a result, the disk cartridge and the disk storage apparatus become thicker, which becomes a bar to downsize the disk storage apparatus.
Since the suspensions 112 are arranged in an in-line fashion relative to the actuator arm 111, the suspensions 112 are easily influenced by a torsion mode which is one of a resonance of the suspension. Therefore, there is the possibility that the R/W heads H become unstable state relative to the hard disk surfaces and hence the reading/writing operations are prevented from being carried out correctly.
Since a concave portion at the fork-shaped portion of the ramp 114 is opened toward the hard disk 124 side, in a state that the disk cartridge 120 is not loaded, when the actuator arm 111 is rotated because of some cause and then rotated backward, the suspensions 112a, 112b with the R/W heads H are inserted into and engaged with the concave portion of the ramp 114, which disables the actuator arm 111 to be further rotated backward and may damage the R/W heads H.
Since the actuator arm 111 is inserted into the disk cartridge 120, a corner of a portion of the R/W head attached with a wiring by soldering is made smaller in order to prevent it from interfering with the disk cartridge 120, a workability of wiring, soldering and so on becomes unsatisfactory.
Since the disk cartridge 120 must be inserted without interfering with the actuator arm 111, the ramp 114 and so on when it is loaded, high accuracy is required for a guide mechanism, which leads to increase of the manufacturing costs of the above-mentioned disk storage apparatus.